This invention relates to unscramblers for bowl- and cup-shaped articles, such as may be produced by moulding in plastics material and intended for use as bases for plastic bottles or covers for aerosol or other spray cans or the like, all hereinafter referred to as "lightweight cup- and bowl-shaped articles".
Currently such articles are delivered from a moulding machine into a hopper-like reservoir from which they are "unscrambled" and presented to a further manufacturing process by means of an elevating conveyor that has inclined ledges or "flights". As the conveyor moves upwardly through the mass of articles in the reservoir, the articles are engaged by the ledges or flights. The elevator is so inclined that articles "correctly" engaged, i.e. with their bases against the conveyor surface, are elevated to the top of the conveyor, but articles which are incorrectly engaged fall off back into the reservoir. By "incorrectly engaged" is meant either that the articles are stacked or that their rims, rather than their bases, are facing the conveyor. Either way, the centre of gravity will lie the wrong side of the ledge or flight of the conveyor.
However, reservoirs and unscramblers of this type have numerous problems, not least among which is the problem of stacking, which is aggravated by the depth of articles which bears down on the lowermost articles in the reservoir. Also of considerable importance is the physical size of the reservoir--limited to some extent, anyway, by the packing problem that causes stacking which cannot be broken up. Should the supplying machine break down, it is necessary to hand feed the reservoir from previously reserved stocks of articles in order to keep machines downstream of the reservoir in production. This is inconvenient and expensive.